On 4 May 1986, just a few days after the initial disaster, mechanical engineer Alexei Ananenko, senior engineer Valeri Bespalov and shift supervisor Boris Baranov stepped forward to undertake a mission that many considered to be suicide. They were advised that if they did not survive, their families would be taken care of. The outcome of their mission would decide the fate of millions of people; its importance was unparalleled in its magnitude and represents one of history’s greatest sliding doors moments. So what exactly was their mission?⁠ ⁠ On the day of the disaster and in an effort to control the blazing fire, firefighters pumped water into the nuclear reactor. One of the side effects was that it flooded the basement with radioactive water. This basement contained the valves that when turned, would drain the ‘bubbler pools’ that sat beneath the reactor and which acted as a coolant for the plant.⁠ ⁠ _____⁠ ⁠ Within a few days, it was discovered that molten nuclear material was melt...